Table 5.7 The effects 0/ neurohypophysial pep tides on urine flow , the GFR and
renal tubular water reabsorption in various reptiles
Mechanism
Antidiuresis GFR Tubular H20
deer . Reabsorption
Pep tides
Used :
Crocodilia
Alligator mlssissippiensis'v:
(Alligator)
Chelonia
Pseudemys scripta 3
(Slider turtle)
a) Small dose
b) Large dose
Lacertilia
Trachysaurus rugosus"
(Bobtail goanna)
Ophidia
Natrix sipedon 5 , 6
(Water snake)
+
+
+
+
+
+
+
+
+
+
+
Pit ressin,
Pitocin
N eural lobe
extract from
Pseudemys
Pitocin, Pitressin,
extract from
lizard
Vasotocin
High dose
mesotocin or
oxytocin
+ = effect
- = no effect
IBURGESS et al. (1933)
2SAWYER and SAWYER (1952)
3DANTZLER and SCHMIDT-NIELSEN (1966)
4BENTLEY (1959 b)
5LEBRIE and SUTHERLAND (1962)
6DANTZLER (1967 a)
flow have not been reported, nor has the presence of such pep tides been demonstrated in the circulation.
It is noteworthy that neurohypophysial peptides exert other actions in reptiles.
They may reduce the blood pressure as in Trachysaurus rugosus (WOOLLEY, 1959)
and Natrix sipedon (DANTZLER, 1967 a) but high doses are required, so that these
effects are probably only of pharmacological significance. Vasotocin (in vitro) contracts the oviduct of the turtle, Pseudemys scripta, when it is in an ovulating condition (M UNSICK et al., 1960). LAPOINTE (1969) has shown that vasotocin also
contracts the oviduct of the viviparous island night lizard, Klauberina riversiana,
in v itro. Oxytocin and mesotocin were very much less effective than vasotocin.
It is possible that this action of vasotocin reflects a ph ysiological role for this peptide in reptilian oviposition and parturition just as oxytocin assists the latter process in mammals.
147
renal tubular water reabsorption in various reptiles
Mechanism
Antidiuresis GFR Tubular H20
deer . Reabsorption
Pep tides
Used :
Crocodilia
Alligator mlssissippiensis'v:
(Alligator)
Chelonia
Pseudemys scripta 3
(Slider turtle)
a) Small dose
b) Large dose
Lacertilia
Trachysaurus rugosus"
(Bobtail goanna)
Ophidia
Natrix sipedon 5 , 6
(Water snake)
+
+
+
+
+
+
+
+
+
+
+
Pit ressin,
Pitocin
N eural lobe
extract from
Pseudemys
Pitocin, Pitressin,
extract from
lizard
Vasotocin
High dose
mesotocin or
oxytocin
+ = effect
- = no effect
IBURGESS et al. (1933)
2SAWYER and SAWYER (1952)
3DANTZLER and SCHMIDT-NIELSEN (1966)
4BENTLEY (1959 b)
5LEBRIE and SUTHERLAND (1962)
6DANTZLER (1967 a)
flow have not been reported, nor has the presence of such pep tides been demonstrated in the circulation.
It is noteworthy that neurohypophysial peptides exert other actions in reptiles.
They may reduce the blood pressure as in Trachysaurus rugosus (WOOLLEY, 1959)
and Natrix sipedon (DANTZLER, 1967 a) but high doses are required, so that these
effects are probably only of pharmacological significance. Vasotocin (in vitro) contracts the oviduct of the turtle, Pseudemys scripta, when it is in an ovulating condition (M UNSICK et al., 1960). LAPOINTE (1969) has shown that vasotocin also
contracts the oviduct of the viviparous island night lizard, Klauberina riversiana,
in v itro. Oxytocin and mesotocin were very much less effective than vasotocin.
It is possible that this action of vasotocin reflects a ph ysiological role for this peptide in reptilian oviposition and parturition just as oxytocin assists the latter process in mammals.
147